JP3999830B2 - Balloon catheter - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a balloon catheter used for performing dilatation treatment on a stenosis disorder portion of a blood vessel.
[0002]
[Prior art]
Conventionally, as a kind of balloon catheter used in PTCA (percutaneous coronary angioplasty) or the like, a type called a monorail type or a rapid exchange type as illustrated in FIG. 5A is known.
[0003]
As shown in the cross-sectional view of FIG. 5B, the monorail type balloon catheter 101 includes a first lumen 111 serving as a fluid supply / discharge path for expanding / contracting the balloon 103, and a guide wire. 109, a second lumen 112 serving as an insertion passage is provided, and the second lumen 112 penetrates from a midway position 101a proximal to the balloon 103 to the most distal end portion 101b of the balloon catheter 101. I was allowed to.
[0004]
As a result, as compared with a type of balloon catheter in which the guide wire lumen is penetrated over the entire length of the balloon catheter, even if the length of the portion of the guide wire 109 exposed to the outside of the human body is relatively short, the second is maintained. I was able to pass through the lumen 112.
[0005]
Therefore, when the balloon catheter 101 is inserted into or removed from the body, it is not necessary to use an excessively long guide wire 109 or connect an extension guide wire to the guide wire 109. There is an advantage that the replacement work of 101 can be performed promptly.
[0006]
[Problems to be solved by the invention]
However, the prior art has the following problems.
In the balloon catheter 101, as shown in FIG. 5B, the first lumen 111 and the second lumen 112 are formed in parallel, but the long material having such a cross-sectional shape has a special shape. There is a problem that the balloon catheter becomes relatively expensive because it requires extrusion molding using a mold and is relatively time-consuming to manufacture.
[0007]
In addition, when the first lumen 111 and the second lumen 112 are formed in parallel as described above, the cross-sectional shape is not isotropic, and uneven shrinkage is likely to occur during cooling after extrusion molding. Both the 111 and the second lumen 112 tended to have a lower roundness of the cross section than a general tube lumen. For this reason, for example, with respect to the second lumen 112, as the roundness of the cross section becomes low, the sliding condition between the second lumen 112 and the guide wire 109 is not uniform over the entire circumference. As a result, the operability may change depending on the curved shape of the balloon catheter 101. Further, for example, in the case of the first lumen 111, as the shape becomes flat as shown in the figure, the liquid does not flow smoothly, and the response when the balloon 103 is expanded / contracted is hindered. was there.
[0008]
SUMMARY OF THE INVENTION An object of the present invention is to provide a balloon catheter that has a structure that can be manufactured relatively easily, that can be satisfactorily slipped between the guide wire and the balloon can be responsive.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, the balloon catheter of the present invention is as described in claim 1,
A first tube having a lumen serving as a fluid supply / discharge passage, a second tube having a lumen serving as a guide wire insertion passage, and a fluid supplied / discharged via the lumen of the first tube And a balloon that expands and contracts by
In a state where a part on the distal end side of the first tube and a part on the proximal end side of the second tube are arranged in parallel, the first and second tubes are fixed to each other,
The balloon is fixed to the outer periphery of the second tube with the distal end opening of the first tube communicating with the inside .
Furthermore, it has a lumen that serves as an insertion path for the guide wire, and a part on the distal end side is tapered such that the tip becomes thinner, and the tapered part is externally connected to the distal end side opening of the second tube. A third tube inserted into the lumen of the second tube in a state of protruding to
After the balloon has reached a target indwelling position, blood is allowed to flow through the second tube when the third tube is retracted in a direction of being pulled out from the second tube. .
[0010]
The balloon catheter according to claim 2
Inside the balloon, a metal wire is spirally fixed to the outer periphery of the second tube.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
According to the balloon catheter of the first aspect, as described above, the first and second tubes formed separately are fixed to each other. These individual tubes have a very common shape with a single lumen and can be molded relatively easily. Therefore, compared with the conventional monorail type balloon catheter, the labor for manufacturing is remarkably reduced, and the balloon catheter can be provided at a relatively low cost.
[0013]
In addition, the first and second tubes are each of a very general shape, and there is no thickness deviation at all, so the roundness of the lumen of each tube should be made relatively easy. Can do. Therefore, with respect to the lumen serving as the guide wire insertion passage, the degree of sliding between the guide wire and the guide wire is uniform over the entire circumference, and good operability is ensured. Further, with respect to the lumen serving as a fluid supply / discharge path, the resistance that the fluid receives when flowing can be minimized, and the responsiveness when the balloon is expanded / deflated is improved.
[0014]
Further, in the case where the fluid supply / discharge passage and the guide wire insertion passage are integrally formed as in the prior art, it is necessary to select a material suitable for both fluid supply / discharge and guide wire insertion. Although there was a drawback that the width was narrow, in the case of the balloon catheter of the present invention, the first tube was selected to be suitable for fluid supply and discharge, and the second tube was suitable for insertion of the guide wire. Therefore, there is an advantage that the range of selection for each tube is wider than the conventional one. Incidentally, the first tube is preferably made of a resin material such as polyimide, nylon, polyethylene, or polypropylene because the tube has good moldability and the roundness of the lumen is easily secured. The second tube is preferably made of a resin material such as nylon, polyethylene, or fluororesin because the guidewire has a high slidability and can easily secure a lumen.
In addition, the balloon catheter of the present invention can send blood to the peripheral side of the blood vessel even when the balloon is expanded via the second tube. When blood is flowed through the second tube in this way, a larger amount of blood flows more smoothly as the second tube is thicker.
Here, if the second tube is simply made thicker, the tip of the second tube is easily caught by the blood vessel wall when the balloon catheter is advanced in the blood vessel, and as a result, it is difficult to advance the balloon catheter. There is a harmful effect that it becomes difficult to enter into a stenosis in a blood vessel.
In this regard, in the balloon catheter of the present invention, even if the diameter of the second tube is relatively large, the tapered third tube protrudes from the tip of the second tube. When inserted, the tip of the third tube advances smoothly in the blood vessel and smoothly enters the stenosis. Further, since the second tube only follows the third tube, the second tube smoothly advances in the blood vessel and smoothly enters the stenosis.
Then, after the balloon has reached the target indwelling position, if only the third tube is retracted, blood flows through the second tube. In particular, as described above, by providing the third tube, the second tube can be made relatively thick, so that the blood flow becomes extremely smooth.
[0015]
By the way, since the inside of the balloon is at a relatively high pressure, the second tube is not only excellent in the insertion property of the guide wire, but usually needs to be strong enough not to be crushed even when high pressure is applied from the outside. Become.
In this regard, as described in claim 2, when the metal wire is fixed to the outer periphery of the second tube in a spiral shape inside the balloon, the metal wire fixed to the second tube is The strength against crushing of the second tube is increased without impairing the flexibility of bending of the tube. As a result, the second tube will not be crushed even when the inside of the balloon is at a high pressure. For example, the second tube itself does not take into account the strength against crushed, and the friction with the guide wire is more It is possible to select a material that is small.
[0019]
The third tube is preferably made of a material such as nylon, polyethylene, or fluororesin because it has high strength and can ensure good slipperiness.
In addition, the third tube has a tapered shape at the distal end side, but the shape gradually narrows toward the distal end side as well as a part where the thickness does not change or a constricted part is formed. Even if a portion that is partially thickened toward the tip side is included, if the shape is that the tip side is thin as a whole, it is included in the tapered shape.
[0020]
Next, to the embodiment of the present invention to more clearly be described with reference to the accompanying drawings a specific example of a balloon catheter. Of the specific examples described below , the third specific example corresponds to an example of an embodiment of the present invention . However, embodiments of the present invention is not limited to specific example illustrated below.
[0021]
[First example]
As shown in FIG. 1, the balloon catheter 1 includes a first tube 11 having a lumen serving as a fluid supply / discharge path, a second tube 12 having a lumen serving as an insertion path for the guide wire 19, and a first tube. A balloon 13 that is expanded / contracted by a fluid supplied and discharged through the lumen of 11, a connector 14 for connecting to the fluid supply source, and the position of the balloon 13 when it is inserted into the body to X-rays And a marker 15 provided for confirmation.
[0022]
Among these, the first tube 11 and the second tube 12 are tube materials formed separately, respectively, a part 11 a on the distal end side of the first tube 11 and a part on the proximal end side of the second tube 12. 12a are fixed to each other in a state of being arranged in parallel as shown in FIG. In this fixing, as shown in FIG. 2A, an adhesive 16 is interposed between the first tube 11 and the second tube 12, and the outer periphery thereof is covered with a heat-shrinkable film 17 and heated. It is tightened by. In addition, as shown in FIG.2 (b), you may adhere both using only the adhesive agent 16. FIG.
[0023]
The balloon 13 is fixed to the outer periphery of the second tube 12 with the distal end opening 11b of the first tube 11 communicating with the inside.
The first tube 11 is required to be relatively rigid on the proximal end side to transmit force to the distal end side, whereas on the distal end side, the first tube 11 smoothly advances in a tortuous blood vessel. Therefore, since flexibility is required, it is gradually thinned in three stages from the proximal end side to the distal end side, and further, a reinforcing metal wire (from the proximal end side to the middle part) (Not shown).
[0024]
According to the balloon catheter 1 configured in this manner, the total length of the second tube 12 is considerably shorter than the total length of the balloon catheter 1, so that a so-called monorail type structure is formed and the guide wire 19 is exposed outside the human body. Even if the length of the portion is relatively short, it can be passed through the second tube 12. Therefore, when the balloon catheter 1 is inserted into the body or removed from the body, there is no need to use an excessively long guide wire 19 or connect an extension guide wire to the guide wire 19. 1 replacement work etc. can be carried out promptly.
[0025]
In particular, each of the first tube 11 and the second tube 12 has a relatively easily moldable shape and a relatively simple structure in which the first tube 11 and the second tube 12 are fixed to each other. Therefore, compared to a conventional monorail type balloon catheter, The manufacturing effort is greatly reduced.
[0026]
Further, the roundness of the lumens of the first tube 11 and the second tube 12 can be relatively easily increased as compared with a conventional monorail type balloon catheter. Therefore, the degree of sliding with the guide wire 19 is uniform over the entire circumference, and good operability is ensured. Further, the resistance that the fluid undergoes when flowing can be minimized, and the responsiveness when the balloon 13 is expanded / contracted is improved.
[0027]
Furthermore, the first tube 11 is formed with a material suitable for fluid supply / discharge, and the second tube 12 is formed with a material suitable for insertion of a guide wire, and both may be fixed. Wide range of materials selection.
[Second specific example]
Next, a second specific example will be described. In the following description, members similar to those of the first specific example are denoted by the same reference numerals, and description thereof is omitted.
[0028]
As shown in FIG. 3, the balloon catheter 2 includes a first tube 11, a second tube 12, a balloon 13, a connector 14, and the like.
In particular, inside the balloon 13, the metal wire 21 is spirally fixed to the outer periphery of the second tube 12.
[0029]
According to the balloon catheter 2 configured as described above, the metal wire 21 increases the strength against crushing of the second tube 12 without impairing the flexibility with respect to the bending of the second tube 12. As a result, even if the inside of the balloon 13 becomes high pressure, the second tube 12 does not collapse. Accordingly, the second tube 12 can be selected from a material that reduces friction with the guide wire without particularly considering the strength against crushing.
[0030]
[Third example]
Next, a third specific example will be described.
As shown in FIGS. 4A and 4B, the balloon catheter 3 includes a first tube 11, a second tube 12, a balloon 13, a connector 14, a marker 15, and the like.
[0031]
In particular, the third tube 23 is inserted into the lumen of the second tube 12. The third tube 23 has a lumen serving as an insertion path for the guide wire 19 and can be pulled out from the second tube 12 along the guide wire 19 to the hand side as shown in FIG. 4B. . Further, a portion 23a on the distal end side of the third tube 23 has a tapered shape that becomes thinner toward the tip, and this tapered portion 23a is far from the second tube 12 in the initial state shown in FIG. Projecting outward from the distal end side opening 12b. Further, several side holes 25 are formed on the side surface of the second tube 12 and communicate with the inner cavity of the second tube 12.
[0032]
The balloon catheter 3 configured as described above is advanced in the initial state shown in FIG. 4A along the guide wire 19 that has passed through the lesion in the blood vessel in advance. At this time, since the tapered third tube 23 projects from the distal end side of the balloon catheter 3, the balloon catheter 3 can be smoothly advanced inside the blood vessel. Penetrates smoothly.
[0033]
When the balloon 13 reaches the lesioned part, a liquid is injected through the first tube 11 to expand the balloon 13 and expand the lesioned part. When the balloon 13 is inflated, the third tube 23 is retracted from the position shown in FIG. 4 (a) to the position shown in FIG. 4 (b). Thereby, blood flows as shown by an arrow in FIG. 4B, and the blood is sent to the peripheral side of the blood vessel. In particular, in this balloon catheter 3, the inner diameter of the second tube 12 is relatively large, so that a large amount of blood can flow more smoothly. Normally, when the second tube 12 having such a large diameter is opened at the tip of the balloon catheter 3, it is not easy to guide the balloon catheter 3 in the blood vessel or introduce it into a stenosis disorder part. In the case of 3, the tip of the third tube 23 is tapered, and in the initial state shown in FIG. 4 (a), guidance in the blood vessel and introduction into the stenosis disorder part can be carried out satisfactorily.
[0034]
Although specific examples of the present invention have been described above, various specific configurations of the present invention are possible in addition to the specific examples.
For example, the metal wire 21 shown in the second specific example can also be adopted in the balloon catheter 3 of the third specific example.
[0035]
【The invention's effect】
As described above, according to the balloon catheter of the present invention, since the first tube and the second tube are separately molded and fixed, they can be manufactured relatively easily in view of the structure. In addition, since an optimal material can be selected for each tube, sliding between the guide wire and the balloon can be improved.
In addition, a large amount of blood can be flowed more smoothly through the second tube, and can be easily operated with the third tube when guiding in a blood vessel or invading into a stenosis.
[0036]
Moreover, according to the balloon catheter of Claim 2, the intensity | strength with respect to the crushing inside a balloon can be improved irrespective of the material of a 2nd tube .
[Brief description of the drawings]
FIG. 1 is a side view showing a balloon catheter of a first specific example.
FIG. 2A is a cross-sectional view taken along the line AA of the balloon catheter of the first specific example, and FIG. 2B is a cross-sectional view showing a modified example thereof.
FIG. 3 is a side view showing a balloon catheter of a second specific example.
4A and 4B show a balloon catheter of a third specific example, in which FIG. 4A is a side view in an initial state, and FIG. 4B is a side view in a state in which a third tube is pulled out.
5A and 5B show a conventional monorail type balloon catheter, in which FIG. 5A is a side view thereof, and FIG. 5B is a cross-sectional view taken along the line BB.
[Explanation of symbols]
1, 2, 3 ... Balloon catheter, 11 ... First tube, 12 ... Second tube, 13 ... Balloon, 14 ... Connector, 15 ... Marker, 16 ... Adhesion Agent, 17 ... film, 19 ... guide wire, 21 ... metal wire, 23 ... third tube, 25 ... side hole.

Claims (2)

A first tube having a lumen serving as a fluid supply / discharge passage, a second tube having a lumen serving as a guide wire insertion passage, and a fluid supplied / discharged via the lumen of the first tube And a balloon that expands and contracts by
In a state where a part on the distal end side of the first tube and a part on the proximal end side of the second tube are arranged in parallel, the first and second tubes are fixed to each other,
The balloon is fixed to the outer periphery of the second tube with the distal end opening of the first tube communicating with the inside .
Furthermore, it has a lumen that serves as an insertion path for the guide wire, and a part on the distal end side is tapered such that the tip becomes thinner, and the tapered part is externally connected to the distal end side opening of the second tube. A third tube inserted into the lumen of the second tube in a state of protruding to
After the balloon has reached a target indwelling position, blood is allowed to flow through the second tube when the third tube is retracted in a direction of being pulled out from the second tube. Balloon catheter. The balloon catheter according to claim 1,
Inside the balloon, a metal wire is spirally fixed to the outer periphery of the second tube.

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